Chronically elevated levels of PTH might also lead to bone resorption and demineralization that resemble the bone changes seen in rickets in children with irregular and widened metaphyses, Madelung-like deformity or primary hyperparathyroidism, including brown tumours (a bone lesion that can occur when osteoclast activity due to hyperparathyroidism is excessive)72. The gene discussed is PTH; the disease is hyperparathyroidism.